Genesis 15:13; Genesis 15:16; Genesis 15:18

13 The Lord said to him, "Your descendants will be strangers in a foreign land; they will be slaves there and will be treated cruelly for four hundred years.
16 It will be four generations before your descendants come back here, because I will not drive out the Amorites until they become so wicked that they must be punished."
18 Then and there the Lord made a covenant with Abram. He said, "I promise to give your descendants all this land from the border of Egypt to the Euphrates River,